Jet Production Rates in Association with W and Z Bosons in pp Collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports measurements of jet production rates associated with W and Z bosons in proton-proton collisions at 7 TeV, testing perturbative-QCD predictions and exploring potential signs of new physics.

Contribution

It provides the first detailed measurements of jet rates with W and Z bosons at 7 TeV, including ratios, asymmetries, and a test of Berends--Giele scaling, comparing results with theoretical predictions.

Findings

Results agree with perturbative-QCD calculations.

Measured W/Z cross section ratios match predictions.

No evidence of deviations indicating new physics.

Abstract

Measurements of jet production rates in association with W and Z bosons for jet transverse momenta above 30 GeV are reported, using a sample of proton-proton collision events recorded by CMS at sqrt(s) = 7 TeV, corresponding to an integrated luminosity of 36 inverse picobarns. The study includes the measurement of the normalized inclusive rates of jets sigma(V + >= n jets)/sigma(V), where V represents either a W or a Z. In addition, the ratio of W to Z cross sections and the W charge asymmetry as a function of the number of associated jets are measured. A test of Berends--Giele scaling at sqrt(s) = 7 TeV is also presented. The measurements provide a stringent test of perturbative-QCD calculations and are sensitive to the possible presence of new physics. The results are in agreement with the predictions of a simulation that uses explicit matrix element calculations for final states with jets.